KANSAS CITY, Mo. (AP) After Harrison Butker missed the first field-goal attempt of his NFL career, Chiefs coach Andy Reid walked over to the rookie and prepared to instill a little bit of confidence.

"He said: `I got it. I got it. I was just off a tad,'" Reid recalled of their brief exchange. "He kind of gives you that feeling that everything's going to be OK."

Better than just "OK."

Butker responded to his first-half miss Monday night by drilling three field goals in the second half, the last a go-ahead 43-yarder with 8 seconds left that helped Kansas City beat the Washington Redskins 29-20 and remain the only unbeaten team in the NFL.

"I didn't have butterflies. I felt confident," said Butker, who was claimed off the Carolina practice squad to replace injured kicker Cairo Santos. "I knew it was going to come down to a field goal. I felt pretty calm. I was excited; I wasn't nervous."

The Chiefs (4-0) put an exclamation point on the win when linebacker Justin Houston picked up a fumble as the Redskins (2-2) were trying to keep the game alive and returned it for a game-ending touchdown.

The last time there was only one unbeaten team through the first four weeks of the season was 2010, when the Chiefs were the final team standing. They went on to win the AFC West.

"I mean, it's the NFL. It's any given Sunday for a reason," said Chiefs tight end Travis Kelce, who had seven catches for 111 yards and a score. "All these teams are scheming everybody up. It's a testament to this team for especially not only being 4-0, but the way we've won."

Alex Smith threw for 293 yards with touchdowns on the ground and through the air, and his 37-yard strike to Albert Wilson on a broken play set up Butker's go-ahead kick. Kareem Hunt added 101 yards on the ground for the rookie's fourth straight 100-yard effort.

"Winning is more meaningful," Hunt said with a smile. "I could have 50 yards as long as we win."

Kirk Cousins had 220 yards passing and two touchdowns for Washington, but his throw to the end zone with 50 seconds left was dropped by Josh Doctson and forced the Redskins to kick a field goal.

That missed opportunity came back to haunt them less than a minute later.

"We'll go back and try to look at different plays throughout the game that could have made a big difference," Cousins said. "A tough one to lose. Felt like we had a chance there and didn't get it done."

The Redskins stunned the Chiefs early when Cousins found Terrelle Pryor over star cornerback Marcus Peters for a 44-yard touchdown pass, then drove to the goal line before settling for a field goal.

But the plucky Chiefs slowly fought their way back into the game.

Smith started to find his athletic tight end down the seam, then hit Kelce with a 17-yard TD strike late in the first half. The two connected again on third down shortly after the break, and Smith scored a few plays later when he fooled the defense with a quarterback-keeper.

The Redskins needed less than 2 minutes to answer: Cousins' 69-yard pass to Vernon Davis set up a short throw to Ryan Grant, who also beat Peters, for a touchdown and a 17-14 lead.

"I was looking up and I'm like, `Man, we've got all backups in,'" Redskins safety D.J. Swearinger said. "If your number is called, you've got to step up. We've got to get better at that as well."

It was 17-all after Butker made his first field goal, and his 32-yard kick gave Kansas City the lead back. The Redskins tied the game once more when Dustin Hopkins hit from 40 yards with 47 seconds left, but that turned out to be enough time to get Butker in position for the winning kick.

"He has a leg," Hunt said, "so I wasn't too worried. Just make it routine. He had a rough start but honestly, I believed in him, that he was going to bounce back."

PREGAME TRIBUTE

Flags flew at half-staff and there was a moment of silence before the game for victims of the Las Vegas shooting. The Redskins then locked arms for the national anthem, while everyone on the Chiefs' side stood with the exception of cornerback Peters and linebacker Ukeme Eligwe.

INJURY WATCH

Norman left in the second quarter with a rib injury and could miss several weeks, while running back Rob Kelley joined the Redskins' defensive guys on the sideline with an ankle injury. The Chiefs lost right guard Laurent Duvernay-Tardif, who was sidelined by a left knee injury on their second offensive play.

UP NEXT

Washington gets a bye week before hosting San Francisco on Oct. 13.

Kansas City returns to the road to face Houston on Sunday night.

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